WO1997039989A1

WO1997039989A1 - Mould cooling device in the glass making industry, relevant mould machining process and fitness process of said cooling device in different moulds for changing the production from a glass container to another

Info

Publication number: WO1997039989A1
Application number: PCT/IT1996/000080
Authority: WO
Inventors: Ambrogio Morettin
Original assignee: Aziende Vetrarie Industriali Ricciardi-Avir S.P.A.
Priority date: 1996-04-22
Filing date: 1996-04-22
Publication date: 1997-10-30
Also published as: DE69623136D1; EP0895509A1; ES2181881T3; DE69623136T2; ATE222570T1; PT895509E; EP0895509B1; AU5512896A

Abstract

A mould cooling device is based on air which runs through an annular recess (17) and axial internal conducts (19, 21) with an upper and a lower portion so that the cooling process can start from the middle axial development of the mould; whenever a different kind of bottle is to be manufactured, height adjusting means (34, 38) of air compressed chamber (9, 10) allow this chamber to co-operate with a plurality of different moulds (1).

Description

MOULD COOLING DEVICE IN THE GLASS MAKING INDUSTRY. RELE¬ VANT MOULD MACHINING PROCESS AND FITNESS PROCESS OF SAID COOLING DEVICE IN DIFFERENT MOULDS FOR CHANGING THE PRODUCTION FROM A GLASS CONTAINER TO ANOTHER.

The present invention relates to a mould cooling device in the glass making industry, said mould being adapted to be¬ long to the blank or blow mould class, comprising a compressed air chamber, said chamber being adapted to be fed by an air pipe and being adapted to feed an annular recess of said moulds, said recess being adapted to feed cooling air into a plurality of axial internal conducts of said moulds, said conducts being adapted to comprise an upper and a lower portion with respect to an axial development of said mould.

One of the most critical problems in the hollow glass making industry is made by the cooling process both of blank and blow moulds, because several aspects, which regard quality and quantity consequences of glass production, depend on them. Indeed, it is well known that, if the cooling process is not obtained according to an actually uniform way along the development of, at first, the parison, and, then, of the finished product (i.e. in the blank and in the blow mould), the risk can rise not only to extend, beyond economically suitable reasons, the time required by the production cy¬ cle, but also to reach a too high percentage of scraps. Said scraps are mostly due to cracks, which are caused by a not uniform, and therefore critical, distribution of an internal stress into the walls of the finished product. Indeed, the glass gob, which falls into the blank mould, meets with a first obstruction on the internal mould wall, in correspondence of its portion, where the parison body is tapering to the neck. Said mould portion gets warmer than the other portions and, consequently, it spoils and wears out more than the other internal walls of the mould.Indeed, the glass gob overheats the portion of the internal wall, which it meets and causes the removal of the detaching film from this portion of the internal mould wall, whereby the gob sticks to said wall portion and causes its consequent spoiling.

A known cooling device provides a plurality of conducts, which are internally and axially arranged with respect to the development of the blank and blow moulds. The cooling air is adapted to unidirectionally flow along said con- ducts. In the blank moulds the chamber, which is fed by the compressed air and which is feeding the cooling conducts, is situated close to the mould head, which the gob is inserted through, whereas in the blow moulds the chamber, which is fed by the compressed air, is situated in correspondence of the mould bottom. The air, after cooling the mould, leaves from the opposite direction of the mould.

Consequently, the cooling process starts involving in both of moulds, at first the bottom respectively of the parison and of the bottle, then their intermediate portions and at last their necks; therefore the finished product is cooled in a not uniform way, whereby an internal stress rises, which makes the bottles crack and causes their scraps. It is to be pointed out that, as far as the bottle forming process is concerned, it is dangerous to cool, especially in the blow moulds, at first and more intensively the bottle bottom rather than the other portions of the bottle. Indeed it is well known that an excessive cooling process of the bottle bottom emphasizes the thermic unbalance and causes an internal stress in correspondence of the joint between the bottom and the vertical walls of the mould, to prejudice of the seal of the same bottle.

A further device, which was developed afterwards with regards to the previously described device, provides a splitting of the internal cooling conducts into an upper and a lower portion of the same conducts. They are fed by air, which comes from an annular recess. Said recess is substantially concentric with reference to the axial development of the mould and is placed in a substantial correspondence of the middle of the mould axial development.

The cooling air, starting from here, is directed towards the upper and the lower portion of the mould. Said device is adapted to improve the homogeneous cooling process of the mould in its different portions, whereas the previously described device makes cool more the upper portion of the blank mould and the lower portion of the blow mould with respect to the opposite portions of the moulds. In addition said device presents a further drawback: it relates to the high costs, which are required by substitution of the most old equipments (moulds and mould-holders, which belonged to the previous technological solutions, relating both to moulds with axial cooling conducts and to moulds without any cooling conducts). Consequently, the introduction of the splitted conducts, which are to be axially obtained for the ' cooling process of the moulds, requires high invest¬ ments and the solution of many, not only economical, difficulties, whenever the plants should be up-to-dated according to the modern technologies. A further problem of technological kind should be added to the economical and financial difficulties, which were just described: indeed, it often happens that an equipment, which is manufacturing bottles of a certain shape and of a certain dimension, should change from the production of certain bottles to the production of different bottles. As the change should be made in a quite quick way, the minimum replacement of toolings is required (such a requirement can be satisfied just if the operating toolings can be again used thanks to small traverses and changes). For instance, the change of production can regard a dimen¬ sional change, especially in axial terms, of a bottle. In such a case, the change of blank and blow moulds, as well as the axial (with reference to the mould) replacement of the compressed air chamber are required, said chamber being adapted to feed the axial conducts of the mould with coo¬ ling air.

With reference to a parison or to a finished bottle, where the axial developement of the neck is substantially narrow with respect to the body development, the compressed air chamber and, therefore, the corresponding mould room, which the conducts of cooling air are derived from, can be placed in a substantially middle axial position of the mould, whereas, if the shape of the parison and of the finished bottle presents an axial neck development, which is sub- stantial with respect to the bottle body, the compressed air chamber and the corresponding mould room, which the conducts of cooling air are derived from, should be placed in an axial position, which is substantially close respec¬ tively to the parison- and to the bottle-bottom. Therefore it is apparent that a change of production can require the replacement of the mould, of the compressed air chamber, of the relevant holders, and so on. Total times, which are substantially long, are required by the equipment repla¬ cements. The total costs, which are due to the investment in complete and specific equipment for each kind of bottles to be produced, are substantial, too.

A problem, which the device according to the invention intends to solve is to allow to use, as much as possible, the operating equipment, reducing to a minimum the relevant investment, whenever a plant for the production of glass containers (starting from a plant with externally cooled moulds or with moulds, which are cooled by unidirectional axial conducts) should be provided with moulds, which are cooled by splitted axial conducts, so that the cooling air is blown starting from a substantially middle position with regard to the axial development of thie mould. Such a result could be obviously obtained, if simple machinings are provided, for instance drill and mill machinings, which can obtain the internal conducts and the annular recess connected to the compressed air chamber.

A further aim to join the previous one, concerns the possibility to make the production change of bottle in sub¬ stantially quick times, reducing to a minimum the replacement of equipments, which are necessary for reaching such a production change.

The described problems are solved by the device according to the invention, which is characterized by height adjustment means (34,38) of said compressed air chamber (9,10) with respect to corresponding annular recess (17) of a plurality of different moulds (1), each one of said moulds being adapted to manufacture a specific bottle, whereby said chamber (9,10) is adapted to co-operate with said plurality of moulds (1).

Said and further characteristics will be apparent from the following description and from the alleged drawings, wherein:

Fig.l represents a perspective view of an opened mould, which is made of two couples of blank mould halves; Fig.2 represents a perspective view of a closed blank mould, which istmade of two couples of blank mould halves; Fig.3 represents a perspective view of the equipment to be applied to a double blank mold,i.e. to a blank mould, which is made of two couples of mould halves; Fig.4 represents a partial perspective view of a cooling device, which is applied to a double blank mould, where just one mould half is present;

Fig.5 represents a perspective view of a mould half in a blank mould;

Fig.6 represents a plan view of a detail of the device according to the invention.

D E S C R I P T I O N The device according to the invention is adapted to be applied, with the same substantial rules, to the blank and to the blow moulds in the glass making industry. The present embodiment is dealing just with the cooling device, which can be applied to the blank moulds, but it is to be pointed out that the same cooling device can be automatically extended to the blow moulds, whereby the relevant description is getting shorter and more simple by limiting it to the blank moulds.

On the basis of this limitation of description, but not of application, the device according to the invention comprises two air pipes, which are adapted to feed two douple mould halves A and B. A blank mould 1 (Fig.l) is ma¬ de of these mould halves A and B. Said air pipes comprise an element 2, which is connected, in a way known per se, to a device for the production of compressed air, which is not represented in the drawings. A relevant articulated joint as well as a telescopic joint are not represented in the drawings, too. The element 2 comprises also a telescopic joint 3-3a (Figs.1,2,3) , which is connected, by means of an articulated joint known per se, to a tubular element 4. This latter is adapted to telescopically slide inside the rectangu.l seat, not represented in the drawings, of a block 5 (Figs.1,2), which is integrally connected to two side elements 6 (Fig.2). Said elements present a cut along a transverse line 6a, in order to allow a loosening or a loc¬ king, thanks to two screws 6b, of the tubular element 4 on the block 5. All this in order to allow, as it will be apparent later on, an adjustment along the height of the cooling device in the blank and blow moulds for manufacturing different kinds of bottles, which can differ each one from the others not only in their shapes, but especially in their axial development.

The upper portion of block 5 presents a flange 7, which is screwed by means of two screws 8 (just one of them is represented in Fig.2) to a shell half 9 This latter, as well as a further shell half 10, represents the compressed air chamber of the device according to the invention, which is applied to the blank mould 1.

As far as the blank mould 1 is represented in detail in Fig.4 (which shows just a mould half A), the compressed air chamber, which is made of the shell half 9, is just repre- sented on the left side of said blank mould. Indeed, this mould is a double blank mould, which is made of two mould halves A, which two mould halves B should correspond to. Mould halves A and B are represented in Fig.l. The shell half 9 presents a recess 16 (Figs.3,4), which is adapted to co-operate with an annular recess 17 of the blank mould 1 (Fig.5). The recess 17 is provided with a plurality of ho¬ les 18, which extend downwards into conducts 19 (Fig.l) and of holes 20, which extend upwards into conducts 21. The cooling air, which is blown from shell halves 9,10 into the recess 17 of blank mould 1, is splitted in two portions the first one of which, represented in Fig.l by an arrow C, is directed upwards, and the other one, which is represented by an arrow D, is directed downwards. The blank mould 1 (in the same way as the blow mould not represented in the drawings) presents upwards a shoulder 27 (Figs.1,2), which an upper mould-holer insert 28 is adapted to co-operate with. This latter is then controlled by a hinge-arm 29 (see also Fig.3). In the lower part a hinge- arm 31 (Fig.2) is supported by a lower mould-holder insert 32. The hinge-arms 29,31 are connected, each one to the other, by means of a hinge-system 30. A through bolt 33 (Fig.2) crosses the insert 28, the hinge-arm 29, the shell half 9, the lower hinge arm 31 and the lower insert 32. At last, it ends into a screwed seat (not represented in the drawings), which is obtained into the tubular element 4. A spacer 34 (Figs.2,3) is placed between the hinge-arm 29 and the shell half 9, which is made of two half disks 36 (Fig.6). These latter can be coupled, as it will be apparent later on, by means of two screws 37, in order to enclose the bolt 33. Likewise a spacer 38 (Fig.3) is placed between the shell half 9 and the lower hinge-arm 31, in the same way as the spacer 34.

As it will be explained later on, whenever the shell halves 9,lO of the blank mould 1 and of the blow mould (which is not represented in the drawings), should be adjusted to the axial development of a new mould, the new optimal frontal position of the relevant shell halves 9,10 with respect to the annular recess 17 (Fig.5) of the mould, is found by a suitable selection of the axial development of the spacer 34,38. These latter are provided with some different heights, which are just depending on the axial development of the mould and of the optimal positioning of the shell halves 9,10 (which represent the compressed air chamber for feeding the conducts 19,21). Therefore the spacers 34,38 represent the height adjusting means of compressed air chamber 9,10 with respect to the corresponding annular recess 17 of the mould 1. _^

- 12 -

The described mould cooling device is operating as follows: after deciding which kind of glass container is to be produced, the relevant mould 1, which should be used, is selected and arranged on the equipment of Fig.3, having care to place the shoulder 27 of the mould 1 on the insert

28. Meanwhile the spacers 34,38 of the equipment 3 are selected, taking into account the requirement to place the chamber 9.10 in correspondence of the annular recess 17 of the mould 1. The main advantage of the device according to the invention with respect to known similar device, is given by that the described device is providing a total disengagement of the chamber 9,10 from the mould 1. Indeed the mould 1 is resting, i.e. is applied, with the shoulder

27 on the insert 28, with the consequence that the same mould 1 is quite indipendent from the equipment of Fig.3.

The consequent advantage is represented by the fact that, whenever a mould should be replaced with another due to the change of the container to be produced, the so-called

"cage" (the arms 29,31, the upper insert 28 and the lower insert 32) is disengaged from the mould 1, which can be therefore replaced by another mould for the production of a different container, with the advantage that a drawback is avoided: the necessity to change all the equipment whenever the production of a container is changed. It is apparent that the device according to the invention allows a substantial reduction of the equipment investment due to the introduction of the internal bi-directional coo¬ ling process, where the cooling air is blown from a middle axial development of the mould.

It is to be pointed out that the described device is adapted to be applied in a plant for the glass container production belonging to a single, double and triple gob of traditional conception (i.e. which could be provided with external cooling conducts device, or internal cooling uni¬ directional conducts device) .

Now the advantages of the described device with regards to two processes are worth describing: at first, the machining process of blank and blow traditional moulds (both the externally cooled moulds - because lacking in internal cooling conducts - and the moulds, which are provided with unidirectional cooling conducts) in order to modify them and to fit them the new production technology, which pro¬ vides the internal bidirectional cooling process through internal conducts; second, the fitness process of said cooling device in different moulds for changing the production from a glass container to another. As for the first process, it is possible to change from an _

- 14 -

externally cooled mould to a mould cooled with internal cooling conducts, thanks to the following machinings:

1) turning process for the elimination of any finnings in the area, where compressed air chambers are lea¬ ning;

2) milling process in the turned area in order to machine the annular recess 17;

3) drilling process for machining the cooling conducts. As for the second process, the following operations are necessary:

1) milling process of the area, where the compressed air chamber is contacting the mould, as long as the inter¬ nal conducts are reached. At last, to change from the production of a glass container to the production of another container, which presents a different shape and a different axial development, it is necessary:

1) to loosen the screws 6b of the two side elements 6, in order to disengage the tubular element 4 from the block 5; such an operation allows a height fitness,

I with respect of the new mould 1, the so-called "cage" of Fig.3;

2) to change the spacers 34,38 so that the compressed air chamber 9,10 could present its recess 16 in front of the annular recess 17; 3) to lock the screws 6b of the blocks 5.

Claims

C L A I M S

1. Mould cooling device in the glass making industry, said mould being adapted to belong to the blank or blow mould class, comprising a compressed air chamber (9,10), said chamber being adapted to be fed by an air pipe (2,3,3a,4,5) and being adapted to feed an annular recess (17), said annular recess being adapted to feed cooling air into a plurality of axial internal conducts (19,21) of said moulds, said recess being adapted to comprise an upper (21) and a lower (19) portion with respect to an axial development of said mould, characterized by height adjustment means (34,38) of said compressed air chamber (9,10) with respect to corresponding annular recess (17) of a plurality of different moulds (1), each one of said moulds being adapted to manufacture a specific bottle, whereby said chamber (9,10) is adapted to co-operate with said plurality of moulds (1),

2. Device according to Claim 1, characterized in that said device is adapted to be applied in a plant for the glass container production belonging to a single, double and triple gob. i

3. Device according to Claim 1, characterized in that it comprises two air ducts (2, 3-3a,4,5, ) , each one of them being adapted to feed two shell halves (9,10), said shell halves being adapted to represent said compressed air chamber, said chamber being adapted to present a recess (16), said recess being co-operating with an annular recess (17) of the mould (1), in order to feed a plurality of conducts (19,21) for the cooling process of the mould (1).

4. Device according to Claims 1,3, characterized by a cage (29,31 ,28-,321 , which is disengaged from said mould (1), so that the replacement of a mould ( U with another mould due to the change of the container to be produced is made substantially more simple, avoiding in such a manner the necessity to change all the equipment whenever the production of a container is changed.

5. Mould machining and fitness process of the cooling device according to Claims 1-4 in different moulds for fitting them to a new different manufacturing technology, which provides the internal bidirectional cooling processs through internal conducts (19,21), characterized in that it comprises the following machinings:

1) turning process for the elimination of any finnings in the area, where compressed air chambers (9,10) are leaning;

2) milling process in the turned area in order to machine an annular recess (17) and

3) drilling process for maching cooling conducts (19,21)

6. Mould machining and fitness process according to Claim 5, characterized in that it comprises the following machini ngs: 1) milling process of the area, where the compressed air chamber (9,10) is contacting the mould (1), as long as the internal conducts (19,21) are reached.

7. Mould machining and fitness process according to Claims 5,6, characterized in that it comprises the following machinings:

1) to loosen screws (6b) of two side elements i6), in order to disangage a tubular element (4) from a block (5); such an operation allows a height fitness with respect of a new mould (1), a so-called "cage" of Fig.3;

2) to change spacers 34,38, so that the compressed air chamber (9,10) could present its recess (16) in front of the annular recess (17);

3) to lock the screws (6b) of the block (5).